2016年太原市5株人腺病毒53型病毒分离株基因特征分析

Genetic characteristics of five human adenovirus type 53 strains isolated from Taiyuan city in 2016,China

目的对太原市人腺病毒53型(HAdV-53)病毒分离株进行基因特征研究。方法采集2016年山西省眼科医院门诊流行性角膜结膜炎(EKC)病例眼结膜拭子,共计79份,通过病毒分离和3个主要衣壳蛋白基因包括五邻体基座(Penton base)、六邻体(Hexon)和纤维蛋白(Fiber)的序列鉴定,共获得5株HAdV-53病毒株,同时下载GenBank数据库中全球流行的HAdV-53病毒株以及与HAdV-53相同基因来源HAdV病毒株的相应序列,建立3个基因的数据库,分别构建系统进化树,并使用生物信息学软件分析HAdV-53基因特征和分子进化特点。结果5株HAdV-53病毒株与1996—2014年间其他国家流行的HAdV-53病毒株在3个基因上显示了较高的一致性(>99.8%)。所有HAdV-53病毒株在Penton base和Fiber基因上分别与其重组来源基因型HAdV-37和HAdV-8处于同一进化分支,在基因序列上保持了高度一致性;在Hexon基因上,与其重组来源基因型HAdV-22亲缘性关系最近,核苷酸和氨基酸序列与HAdV-22高度同源,但处于不同的进化分支,HAdV-53进化分支的进化速率为3.51×10^-5替换/位点/年。结论HAdV-53目前已成为太原市重要的新的眼部感染性病原体,HAdV-53病毒株Penton base,Hexon和Fiber基因在进化上均具有保守和稳定的特性。

Objective The genetic characteristics of the human adenovirus type 53(HAdV-53)strains isolated from Taiyuan city of Shanxi Province were studied to obtain the baseline data of their molecular characteristics.Methods Conjunctival swabs(n=79)were collected from epidemic keratoconjunctivitis(EKC)patients in Shanxi eye Hospital in 2016,and five HAdV-53 strains were obtained after virus isolation and identification based on the three major capsid genes sequences including Penton base,Hexon and Fiber gene.And the corresponding sequences of global epidemic HAdV-53 strains and the strains with the same genetic origin as HAdV-53 were also downloaded from GenBank database,and then the three gene database were established,respectively.With the database,phylogenetic tree was constructed,and the genetic and molecular evolutionary characteristics were analyzed with bioinformatics software.Results Five HAdV-53 strains in Shanxi Province in 2016 showed high consistency with the HAdV-53 strains prevalent in other countries in 1996-2014(>99.8%).All HAdV-53 strains were in the same evolutionary branch with their recombinant source genotypes(HAdV-37 and HAdV-8)in Penton base and Fiber gene,respectively,and maintained a high degree of consistency in gene sequences.In Hexon gene,HAdV-53 strains were more closed to its recombinant source genotype HAdV-22,the nucleotide and amino acid sequences between two types were highly homologous,while HAdV-53 and HAdV-22 belonged to different evolutionary branches,and the evolution rate of HAdV-53 based on Hexon gene was 3.51×10^-5 substitution/site/year.Conclusion HAdV-53 has become an important new ocular infectious pathogen of Taiyuan.HAdV-53 strain are relatively conservative and stable based on Penton base,Hexon,and Fiber gene.